Currently, approximately 6.0 million patients enter emergency departments each year complaining of chest pain. Approximately, 500,000 patients are immediately dosed as having acute myocardial infarction (MI) based on an ECO, and an additional 500,000 are ultimately diagnosed as having acute MI based on tests based on cardiac enzymes. Approximately l.5 million are ultimately diagnosed with unstable angina and undergo cardiac treatment and monitoring. Unfortunately, approximately 35,000 of these 3.5 million patients are sent home with a missed acute MI diagnosis, and 6,000 of these MI patients die within 48 hours. In addition, 2.1 million of these 3.5 million patients are diagnosed after extensive evaluation and hospital stays. National statistics indicate that approximately $4.0 billion of unnecessary medical costs are incurred annually on these equivocal MI patients. Time is a critical factor in the treatment of acute MI patients. The purpose of the Phase I research is to evaluate the safety, pharmacokinetics, and radiation dosimetry of Tc-99m glucarate and that of Phase ll is to establish the usefulness of this reagent in the emergency department to enable accurate triage of patients with acute MI form chest pain of non- cardiac origin. PROPOSED COMMERCIAL APPLICATION: Tc-99m glucarate can be used to identify acute myocardial infarction patients. The establishment of such a procedure in emergency room should provide a fast rule-in and rule-out of patients with chest-pain and should conserve scarce healthcare resources.